The present invention pertains to a device for holding and/or attaching flat objects to a carrier plate and, in particular for attaching ribbon cables to a carrier plate.
Ribbon cables have a number of conductors with terminals arranged next to each other in a plane. Ribbon cables may be mounted on a thin, electrically insulating carrier layer. They can be set in a manner that saves a lot of space on carrier plates, e.g., on chassis parts of vehicles, on certain, predetermined tracks. Thus, they must be attached at intervals to the carrier plate.
A device is known from French Patent No. 1,593,626, which is meant for holding a flat object, and also for its attachment to a carrier. The device comprises a base plate, on which two L-shaped arms are symmetrically fixed at a distance from each other. The projecting ends of the arms are connected by a three-part bridge, wherein the total length of the bridge is greater than the distance between the two arms. The interconnection portions of the three plate-shaped parts of the bridge are designed to act like hinges relative to each other and also relative to the arm ends, so that the bridge parts can pivot about these interconnections relative to each other and to the arms. The device can assume an open and a closed position. In the open position, the side parts of the bridge form an obtuse angle with the L-shaped arms, and with the side parts and the middle part of the bridge arch over the base plate like a roof. In the closed position, the side parts of the bridge form an acute angle with the L-shaped arms, and the middle part of the bridge contacts the base plate tightly. Means for attaching to a carrier can be provided on the base plate. A flat object can be clamped between the base plate and the middle part of the bridge by setting the object on the base plate with the device in its open state. Then pressure is applied to the articulated parts of the bridge such that the middle part of the bridge is brought into contact with the flat object.
In the French Patent, the device is described for use as a hose bracket. The device in the French Patent is not optimal for the preferred use of the present invention, namely the attachment of ribbon cables to a carrier plate, and in particular to the chassis parts of vehicles. The device can spontaneously open due to, e.g., vibrations or material fatigue, so that the attachment or hold can be unexpectedly released. This is particularly disadvantageous if the device is mounted in a position that is difficult to access or that is practically inaccessible after manufacture of the vehicle, as is normally the case. In addition, through the planar contact of the middle part of the bridge on the base plate or on the interposed object, the contact pressure and thus the reliability of the hold is reduced. In addition, the briefly mentioned use of a screw in the middle of the base plate to attach the device to a carrier is unsatisfactory. The screw interferes with the object to be attached, and in the case of a ribbon cable, it can lead to damage.
The present invention provides a device that permits a long-lasting, reliable hold and attachment, in particular of ribbon cables, to a carrier plate. Spontaneous loosening of the device is not possible. The device can be attached and closed and opened again easily and quickly with little handling and has no parts that could be lost. Damage to the ribbon cable is precluded.
According to the present invention, a base plate has two end sections for attaching to the carrier plate and a middle section that can be brought into contact with the carrier plate or a flat object to be attached to the carrier plate. A snap-in means is provided at the middle part of the bridge. The snap-in means projects downwards and engages a locking hole in the base plate. The snap-in means is preferably snap-in hooks that project downwards. The snap-in means engages the locking hole such that the device is reliably held in its closed position, and a spontaneous disengagement from this position is not possible. The side arrangement of the attachment means precludes damage to the ribbon cable or another flat object.
Support strips that project downwards at an angle are formed at the longitudinal sides of the middle section of the base plate. The longitudinal edges of these support strips extend beyond the bottom edge of the middle section of the base plate. The support strips reduce the contact surface of the device on a ribbon cable or some other flat object to be attached to the carrier plate, so that the contact pressure between the device and the carrier plate is increased, and thus the hold is more reliable.
Preferably, there is a central hump in the middle section of the base plate. The locking hole for the snap-in hooks that project downwards from the middle part of the bridge passes through this hump. The hump can be formed by a central bulge on the top side and a corresponding depression in the bottom side of the middle section of the base plate.
In the middle of each side support strip, there is a slot extending in the longitudinal direction, and the lower opening of the locking hole can be accessed with a tool through this slot. Thus, when required, the snap-in hooks can be disengaged from the locking hole, the ribbon cable can be detached, and the device remains undamaged, and thus, reusable.
Preferably there is a through hole in each of the two end sections of the base plate for attaching the device to the carrier plate. The diameter of and distance between the through holes correspond to the diameter of and the distance between two posts on the carrier plate, and the device is pressed onto these posts for attaching to the carrier plate with these through holes.
These posts on the carrier plate preferably have grooves and/or ribs. Extensions project from the base plate and the ends of the extensions have pointed and angled outer edges that project into the region of the through holes. By pressing the middle part of the bridge down, the extensions are pushed apart and the outer edges of the extensions contact the grooves and/or ribs of the posts, which additionally secures the attachment.